Consequences of the mild January in Berlin
Bees fly across meadows in search of flowers, hedgehogs wake up from their hibernation: what actually heralds the beginning of spring sometimes happens as early as January this year. Mild temperatures throw nature out of rhythm. “Our ecosystem is coordinated,” explains Julian Heiermann, nature conservation expert at the Nature Conservation Union (Nabu). Insects that fly earlier would then also need food plants. “This is usually synchronized in nature. If it gets even more extreme now, and there might be no winter at all at some point, I have concerns that it will get out of sync.”
The temperatures at the beginning of the year have so far been exceptionally mild. “January is expected to be on a constant high in terms of temperature,” wrote the German Weather Service (DWD) after the first week of January. It has been changing for weeks, he said recently. “It feels more like windy fall weather than winter.”
Due to climate change, there are more weather anomalies such as dry, hot summer or warm and dry winters, says Derk Ehlert, wildlife expert at the Berlin Senate Department for the Environment. These changes affect plants and animals differently – but mostly to their detriment. A healthy, strong stock can cope better with such changes, says Ehlert. “But animals and plants weakened by dry summer, heat and drought that could respond.”
The specific effects of the weather vary from animal to animal. The rough control of hibernation and hibernation works through an internal clock, says Heiermann. “But if it’s very mild for a long time, the fine control doesn’t work. This can lead to the animals becoming active even though it is still too early.”
If it is very mild for a long time, then the fine control does not work. This can lead to the animals dying, although it is still too early to become active.
Julian Heiermann, nature conservation expert of the Nature Conservation Union (Nabu)
For example, if a hedgehog wakes up earlier than usual, then it also needs energy earlier. For this he consumes the so-called brown fat, says Ehlert. This can be quickly converted into energy. “When it gets colder again, the animals then lack the energy for the actual start of spring.”
Bees can’t find flowers
But other animals can also have problems in mild temperatures. With honey bees, for example, it can be fatal, says Ehlert. These would then fly off and find no flowers. “Even frogs can spawn too early.”
But mild winters also have winners. “The wild boars are definitely happy about the weather conditions,” says Ehlert. “They get into the ground well and can search for food.” According to experts, birds from northern and eastern Europe also benefit from loose soil and can find more food as a result. “We notice that directly at the feeding places. They are not visited at all because the birds have enough food.”
The wild boar are sure to be happy about the weather conditions.
Derk Ehlert, wildlife expert at the Berlin Senate Department for the Environment
And what about mosquitoes, which are rather annoying for humans? Do they also benefit from the temperatures? “In the case of mosquitoes, there are so-called population waves: if there is a short winter and a late onset of winter at the end of the year, then the mosquitoes produce more generations than in a shorter growing season,” explains Heiermann. “It then quickly increases.” However, it is still too early to draw any conclusions about the coming summer. “It’s true that more insects are surviving the winter, but the question is will they make it through the spring as well.”
Not necessarily the warm January is also a problem for some animals – but possible cold spells after the mild phase. This is also problematic for plants. Late frost events could damage plants that have already sprouted, says Heiermann.
This can also become a problem in agriculture. “When winter crops shoot up in agriculture with mild temperatures earlier in winter, then crops are more sensitive to subsequent frost than when they are small. And that can then lead to crop failures.”
Overall, dryness and drought in summer are a much bigger problem for nature than mild winters, says Ehlert. “As a result, many species are weakened.” Therefore, one should be happy about any rain at the moment. “Good news for January has already arrived, that we have achieved the necessary amount of rain for the first half of January,” he emphasizes. “The more rain falls in the winter months, the more robust nature is in spring.” (dpa)